PARENT SESSION
NEUROENDOCRINOLOGY

Monday, August 2, 2004
10:30 AM–12:30 PM
Buchanan Courtyard

(129) SENSORIAL OVARIAN DENERVATION BY CAPSAICIN TREATMENT MODIFIES ESTRADIOL AND PROGESTERONE SECRETION, DEPENDING ON THE DAY OF THE ESTROUS CYCLE WHEN THE TREATMENT IS PERFORMED.

Trujillo, Angelica ^{1, 2}, Alba, Leticia², Morales, Leticia¹, Dominguez, Roberto¹, ¹ Biology of Reproduction Research Unit, FES Zaragoza, UNAM, Mexico City, Mexico² School of Biology, Benemerita Universidad Autonoma de Puebla, Puebla, Mexico

ABSTRACT- There is evidence that the sensory innervation of the ovaries plays a role in the mechanisms regulating ovarian functions. The objective of this study was to analyze the effects of sensorial denervation by capsaicin (CAP) treatment to adult rats on each day of the estrous cycle on the estradiol (E₂) and progesterone (P₄) serum levels. Groups of animals were injected s.c. with CAP (50 mg/Kg) or vehicle in the day of estrus (E), diestrus 1 (D1), diestrus 2 (D2) or proestrus (P). A group of cyclic animals was used as untouched-control group. Groups of animals (injected and untouched) were autopsied on each day of the estrous cycle. E₂ and P₄ were measured by RIA. E₂ and P₄ serum levels in vehicle-treated rats were similar to the untouched-control group. When the animals were treated with CAP in E, the ovarian hormones serum levels were similar to the untouched-control rats. In comparison with control rats sacrificed at P, an increase in P₄ and E₂ serum levels in rats injected with CAP in D1 was observed (P₄: 18.9±1.6 versus 4.5±1.1 in the untouched-control group (ng/ml); E₂: 46.6±3.3 versus 28.8±6 in the untouched-control group (pg/ml), p<0.05 ANOVA, followed by Tukey′s test). In comparison with animals sacrificed in P or E, the rats injected with the neurotoxin in D2 showed an increment in the E₂ and P₄ serum levels (Animals sacrificed in P- P₄: 15.6±2.6 versus 4.5±1.1 ng/ml in the untouched-control group; E₂:42.6±1.2 versus 28.8±6 pg/ml in the untouched-control group. Animals sacrificed in E- P₄: 8.8±1.4 versus 5.2±0.9 ng/ml in the untouched-control group; E₂: 29.5±13.7 versus 13.7±2.5 pg/ml in the untouched-control group, p<0.05 ANOVA, followed by Tukey′s test). Present results suggest that, the modulation of ovarian secretion exerted by the sensory innervation varies along the estrous cycle. It is possible that some kind of neural information is recorded in the ovary and sent to the central nervous system, where neural signals arising from the hypothalamus and extra-hypothalamic regions, reaching the ovary through the superior ovarian nerve and the ovarian plexus, modulates the ovarian function.

KEY WORDS: progesterone, capsaicin, estradiol, ovary